Building on Arm64 macOS using cmake throws an error.

[sarooptech]

• axmol version: 2.5.9
• devices test on: MacBook Air M3
• developing environments
  • NDK version: r23c
  • Xcode version: 16.3
  • cmake version: 4.0.1
  • VS Code: 1.99.3
  • The default cmake project generator is "Unix Makefiles"

Steps to Reproduce:

1. Create a new project using axmol CLI.
2. Create a build directory and navigate into it using: mkdir build && cd build
3. Generate build files using cmake: cmake ..
4. Build the project using make
5. It will fail to build and throw an error in the axmol/core/media/AvfMediaEngine.mm file, Line number 368.

Solution:

• Replacing __weak with __unsafe_unretained fixes the problem.

Notes:

• Building using the Xcode generator works without any problem.
• I'm using VSCode, which does not use Xcode generator to create a project by default.
• An error is thrown because the project is using ARC-style code with manual memory management for .mm files. For Xcode, it is working fine because the -fobjc-arc flag is applied to the mm files. The proper solution will be to use the same for other builders.

[halx99]

Axmol not support cmake generator other than -GXcode to build apple target platforms.

[sarooptech]

✅ TL;DR

If you're using Ninja on macOS and get ARC (__weak) errors, either:

• Use a workaround with __unsafe_unretained, or
• Switch to the Xcode generator, which fully supports ARC out of the box.

---

To fix the ARC error in my project, I added this:

#if XCODE
    __weak AVPlayer* player = _player;
#else
    __unsafe_unretained AVPlayer* player = _player;
#endif

Axmol doesn’t officially support the Ninja generator on Apple platforms, so I won’t be sending a PR for this.

Personally, I prefer Ninja because it's much faster during development. So I use the workaround above, and switch to the Xcode generator when needed (e.g. for ARC support).

---

✅ Recommended Fix

If you're having the same issue, the better solution is to switch to the Xcode generator.

👉 If you're using VSCode with the CMake Tools extension:

You can change the generator from the settings:

---

👉 If you're using the terminal, you can make Xcode the default generator by adding this line to your shell config (~/.zshrc or ~/.bashrc):

export CMAKE_GENERATOR="Xcode"